type: string
pattern: '^[A-Za-z0-9-_]+[=]{0,2}$'
description: >-
  The API data type BinaryString is a JSON String. The string is a base64url 
  encoding of a string of raw bytes, where padding (character ‘=’) is added at
  the end of the data if needed to ensure that the string is a multiple of 4
  characters. The length restriction indicates the allowed number of characters.